Covers moderate microclimate in calf hutches

A study of reflective barriers on polyethylene calf hutches has shown that the barriers do moderated hutch microclimate and may be useful for reducing solar heating of the hutches, W.R. Binion and T.H. Friend said at JAM 2013.

The cover used in this research consisted of a single layer of 2-sided reflective aluminized polyester film with polyester scrim reinforcement (reflectivity = 95%, R = 2.7). At each of two dairies, six hutches were either un-covered (control) or had reflective covers across the top and sides of the hutch, leaving the front, back and pen exposed. Each hutch had a 1.2 × 1.8-m attached outdoor wire pen.

Calves were allowed ad libitum access to feed and water.

Loggers mounted 20 cm above the flooring, on the interior side of each hutch, recorded interior temperature at 30-minute intervals over 24 days during late August to early September. The mean daily interior peak temperature over the 24-day observation period (40.5 ± 10.0°C) was 4.2 ± 0.2°C less (P < 0.05) in the hutches with the reflective cover than in the un-covered hutches, and did not differ (P = 0.72) between dairies, the researchers said.

During the 10 days of the observation period with the highest peak temperatures (43 ± 7.5°C), reflective covers resulted in an interior hutch temperature 4.7 ± 0.1°C lower (P < 0.001) when compared with the control.

Interior roof temperatures were recorded on 4 different days using an infrared thermometer during the early afternoon. Interior roof temperature (43.3 ± 16.7°C) was 9.3 ± 1.7°C lower (P < 0.001) for the reflective hutches compared with the control.

The highest recorded interior hutch temperatures during the overall sampling period were 50.5°C for control, and 43.5°C for the reflective hutches, the researchers said.